New Liquid Nitrogen Cooling System for emiT Pro New LN System 
emiT Pro

Below are pictures of the new liquid nitrogen cooling system for emiT. This system, built by Quality Cryogenics, is more efficient in its consumption of LN than the previous system. The previous system maintained a constant flow of nitrogen in order to ensure that liquid nitrogen was present at the "danger will". This new system maintains a liquid nitrogen reservoir at the "danger will" by periodically venting the gaseous nitrogen

(fig 1.)Front view of the LN cooling system. The nitrogen flows from left to right. Some details are explained on the left.
  1. This is the automatic vent. The system is automatically vented when too much gas is formed in order to maintain a constant liquid reservoir.
  2. In this chamber, gaseous nitrogen floats to the top from the bayonets. The liquid nitrogen level is maintained by a thermo-couple inside the chamber which monitors the temperature. When too much gas has formed, a Watlow electronic controller opens the vent (detail 1) in order to raise the liquid level. The temperature which corresponds to the liquid level can be set by the user.
  3. These hoses have bayonets on the other end which connect to the proton paddles
  4. ...to LN dewar


(fig 2.) Side view of the system. The dewar can be seen in the background
  1. Here is where the bayonet plugs into the paddle


(fig 3.)Some of the details are illustrated to the left.
  1. Copper end of copper/beryllia rod. This end attaches to the electronics.
  2. The beryllia end which clamps to the "danger will".
  3. The "danger will".
  4. The LN reservoir: the bayonet from the LN cooling system plugs into here.


(fig 4.) The bayonet from the cooling system is shown here plugged into the proton paddle.
  1. The bayonet inserts and screws in here.
  2. This is the same as detail (4) in figure (1).
  3. The "danger will" is located at this point.


(fig 5.) There are 4 jackets (1) which we can place over the unused bayonets.


(fig 6.) The cooling system hooks up to the dewar through this apparatus. There are hook-ups for two dewars so they can be changed without interrupting the nitrogen flow..
  1. Overflow valves


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Last update: July 2, 2001